The results subsequent to an examination of 250 males aged 30-47 suffering from ischemic heart disease and doing strenous mental work are presented. Two variants were used in phenotyping: the first was based on not too high criteria for the cholesterol and triglycerides level (250 and 140 mg%, respectively), the second one having as a groundwork upper limits of the normal value estimated by the authors (250 and 190 mg%, respectively). It was found that, depending upon the actual value of the upper normal limit for triglycerides hyperlipidemia is demonstrable in 64 or 56% of the males. Of most frequent occurrence were the II and IV types of hyperlipoproteinemia with the latter type prevailing in both variants. Most patients with ischemic heart disease demonstrated a fall of alpha-lipoproteins, as ascertained by their separation through disc-electrophoresis in polyacrylamide gel.